BS 6759-1:1984

Foreword
Committees responsible
Specification
Section one. General
1. Scope
2. Definitions
Section two. Material requirements and limitations
3. Pressure containing components
4. Body seat faces and valve disk faces
5. Safety valve springs
6. Bolting for pressure containing joints
Section three. Design and construction
7. General
8. Scantlings
9. Castings
10. Forgings
11. Springs
Section four. Production testing and inspection
12. General
13. Safety precautions
14. Test media
15. Hydraulic test
Section five. Marking
16. Body marking
17. Identification plate
Section six. Performance testing
18. Type testing of safety valves for operating and
     flow characteristics using water, steam, air or
     other gas
19. Tests to determine operating characteristics
20. Tests to determine flow characteristics
21. Determination of coefficient of discharge and
     certified discharge capacity
Section seven. Safety valves for boilers, superheaters,
reheaters and economizers
22. Boilers and superheaters
23. Reheaters and superheaters separated from the
     boiler
24. Safety valves for economizers
25. Operating margins
Appendices
A. Derivation of superheat correction factors
B. Guidance on safety valve mounting
C. Inspection and testing facilities
Tables
1. Helical coil spring materials and mechanical
     properties
2. Minimum duration of hydraulic shell test
3. Values of C relative to values of k
4. Capacity correction factors for back pressure (Kb)
5. Superheat correction factor KSh
Figures
1. Illustration of area definitions
2. Graph for value of constant K, the safety valve
     spring correction factor
3. Compression factor Z as a function of reduced
     pressure pr and reduced temperature Tr

Specifies requirements for safety valves for boiler installations and associated pipework where the steam pressure exceeds 1 bar gauge or, in the case of hot water boilers, where the rating is 44 kW and above.